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List of terms necessary to understand the contents of this guide.


ACL (Access Control List)

A traffic filter of a list of networks and correlated actions used to improve security. Block or allow users to access specific resources.


An EOSIO account is a human-readable name that is stored on the blockchain. It can be owned by an individual or group of individuals depending on the configuration of the permissions. An account is required to transfer or send any valid transaction to the blockchain.

Actions (EOSIO)

Functionality exposed by a smart contract that is exercised by passing the correct parameters through an approved transaction to an EOSIO network.

Actions (Hasura)

Actions are a way to extend the Hasura schema with custom business logic through custom mutations and queries.

Actions can be added to Hasura to handle various use cases, such as data validation, enrichment of data from external sources, and any other complex business logic.

Active Permission

Within account permissions, this is the owner's primary child permission by default. The active permit can perform all the actions of an account other than restructure the permission structure. It is one of the two default permissions that come with a new, proprietary and active account.


A general method of placing tokens in EOS accounts. It is a distribution of a cryptocurrency token or coin, usually free, to numerous wallet addresses.


The Airgrab model is designed to be a more capital efficient way to deploy dApp developer tokens. If you use the Airgrab token, it means you will use your own personal RAM and not the dApp developers like you do in an Airdrop, making it cheaper for the dApp developer.

API (Application Programming Interface)

Set of functions and procedures that allow the creation of applications that access the characteristics or data of an operating system, application or other specific service.



Backend is the data access layer of a software, which is not directly accessible by users, it contains the logic of the application that handles said data. The Backend accesses the server, which is a specialized application that understands the way the browser requests information.


A blacklist is a measure that a blockchain node can take to prevent it from blocking any transaction that has been authorized by a defined list of blocked accounts or any transaction that interacts with a defined list of contracts. Each node can define its own blacklist, which cannot be seen publicly.


Blocks are files where the data belonging to the blockchain is permanently recorded. They store some or all of the most recent transactions that have not yet entered any previous blocks. A block is a permanent store of records that once written cannot be altered or deleted.

Block Explorer

A block explorer is a program or website accessible through a browser that allows a user to search and navigate through the blocks of a blockchain, their contents and their relevant details.

Block Height

It is defined as the number of blocks in the chain between a given block and the first block in the block chain. For example a block height of 500 refers to block number 500 of that chain.

Block One is the company that created the EOSIO software. A producer of highly scalable, high-performance open source software, it is at the forefront of developing the next generation of the Internet.

Block Producer

Block producers are one of's main innovations, they are the decentralized entities that govern the EOSIO blockchain. Rather than being managed by a small number of mining groups, EOSIO will have a constantly changing group of 21 block producers.

Block Rewards

Bitcoin block reward refers to the new bitcoins that are awarded by the blockchain network to eligible cryptocurrency miners for each block they mine successfully.


A growing list of records, called blocks, that are linked by cryptography. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data (usually represented as a Merkle tree).


It is the first DPOS blockchain equipped with IBC. Its goal is to refactor business scenarios with decentralized technology and build a credible blockchain ecosystem that supports billions of users.

Bytecode Canonical

It is used for communication between different data formats. A form of business application integration, it aims to reduce costs and standardize the agreed definitions of data associated with the integration of business systems.


CDT (Contract Development Toolkit)

A complete smart contract development toolkit with a set of tools and utilities necessary for the development of EOSIO Smart Contracts. It provides support for the Gnu and C ++ 11 style by creating a more reliable way to declare your smart contract structure and associated data structures.

Chain ID

A chain ID is a blockchain configuration that affects the formation of an address. The binary transaction link between the address and the chain ID makes it impossible to move transactions between different blockchain networks.


It is the command line tool that connects to the API exposed by nodeos and works to manage the wallet, account, keys, transactions and smart contracts.


The CPU is processing power, the amount of CPU an account has is measured in microseconds (μs), it is known as CPU bandwith, the cleos get account command issues the amount of processing time an account has at its disposal by pressing actions to a contract.



They are digital applications or programs run on a blockchain or P2P computer network instead of a single computer, these are outside the reach and control of a single authority.


A set of practices that combines software development and IT operations. Its goal is to shorten the life cycle of systems development and provide continuous delivery with high-quality software.


A platform to train dapp developers with capabilities to create modern blockchain applications with fast and fluid interfaces that provide exceptional user experiences.


A set of platform as a service products that uses virtualization at the operating system level to deliver software in packages called containers. Containers are isolated from each other and bundle their own software, libraries, and configuration files; they can communicate with each other through well-defined channels. All containers are run by a single core operating system, therefore using fewer resources than virtual machines.


A consensus algorithm developed to secure a blockchain, this by ensuring the representation of transactions within it. DPoS is designed as a technology-based implementation of democracy, using voting and election processes to protect blockchain from centralization and malicious use.



EOS is a decentralized blockchain-based system that enables the development, hosting, and execution of decentralized, commercial-scale applications (dApps) on its platform. EOS supports all the basic functions necessary to enable businesses and individuals to create blockchain-based applications in a similar way to web-based applications, such as providing secure access and authentication, permissions, data hosting, usage management, and communication. between dApps and the internet.


A mobile platform that offers the benefits of EOS to people. It is an easy and secure way to help users access various EOS functions like tokens, voting, resource management, and RAM trading.

EOS Rate

EOS Rate is an open source dApp that enables EOS token holders to rate Block Producers (BP) in just a few clicks. Users can access a rating system and voting portal, making it easy for token holders to make an informed decision.

EOS Studio

EOS Studio is a unified graphical IDE to accelerate dApps development Integrated with various tools necessary for EOSIO.


EOS Costa Rica is a startup derived from the pioneering company Sistemas Edenia Internacional SA, established in 1987 and operating as a blockchain infrastructure provider since 2013. At EOS Costa Rica we manage the infrastructure for EOSIO networks and develop dApps that emphasize individual sovereignty and promote business adoption. We also provide an open platform for developers to innovate, as well as training programs to increase opportunities in the blockchain space.


Eosfinex is a high performance decentralized exchange built on technology. Eosfinex combines the scalability and speed of EOS with Bitfinex's industry leading expertise to deliver a chain exchange built around a fast, transparent and trustless platform for digital asset trading.


EOSIO is a blockchain designed to facilitate the operation of a new type of program called decentralized application (dapp). Its technology attempts to solve historical problems by using blockchains to run dapps, as popular apps have even clogged up the capacity on larger and more developed blockchains, resulting in performance issues for all users.


A library created to easily control the EOS blockchain with Javascript. It can be said that it was made to easily use the EOS HTTP API (nodeos). (web3.js on Ethereum, neon-js on Neo).


A highly accurate block explorer that provides access to accurate, detailed and actionable data on accounts, stocks and block producers.


A block browser, wallet and network monitor all in one. It is designed to be easy, fast and clean.



Trust money (fiat) is a government-issued currency that is not backed by a physical product, such as gold or silver, but by the government that issued it.


Genesis JSON

genesis.json is the file that defines the Genesis block, which is the starting block of the blockchain. This is like the "configuration" of your blockchain. For example, the chain configuration and the level of difficulty to extract blocks.


A platform that provides hosting for version control of software development, in addition, it allows to manage distributed version control and the functionality of source code management, as well as its own characteristics. It provides access control and various collaboration features such as bug tracking, feature requests, task management, and wikis for each project.


An API query language, it uses a runtime to populate those queries with your existing data. GraphQL provides a comprehensive and understandable description of the data in your API, gives customers the power to ask for exactly what they need and nothing else, makes APIs evolve over time, and enables powerful developer tools.



Hackathon is an event (competition) in which computer programmers, graphic designers, interface designers, project managers meet and try to work on projects related to technology and specific problems.


A backend service for custom business logic, integrated with Hasura, using actions.

Hardware Biométrico

These are technological devices that allow biometric data from humans or other objects to be perceived, an example of this is the easy recognition that some security cameras and mobile devices have, also the unlocking of artifacts by means of fingerprints, to mention Some.


Is the process of transforming a string into a fixed-length key or value. A data string will always produce the same hash, so it is used as a means of checking the content of the string against the expected content.


An ultra-fast GraphQL server that offers you real-time GraphQL API over Postgres, with webhook triggers on database events and remote schemas for business logic.

It also helps build Postgres-supported GraphQL applications or gradually move to GraphQL for existing applications that use Postgres.

Head Block

The Head Block is the last block written on the blockchain, stored in reversible blocks.


Is an easy to use command line HTTP client for the API era. It comes with JSON support, syntax highlighting, persistent sessions, wget downloads, plugins, and more.


IAC (Infrastructure as Code)

Is the process of managing computer data centers through machine-readable definition files, rather than physical hardware configuration or interactive configuration tools.

IBC (Inter-Blockchain Communication)

A tool by which multiple blockchains can communicate with each other. This can be used to send tokens from one chain to another, or to expand the capacity of a network by increasing the number of chains running in parallel.

ICO Inter Blockchain Communication

Popular method of distributing the initial supply of coins (tokens) by selling them in exchange for fiat currency or other cryptocurrencies.


Term used to refer to something that cannot be changed.


The mechanism through which new tokens are created on the EOS mainnet. 20% of these are used to pay Block Producers and Standby Producers, with the remainder going into the eosio.saving account.

Inline Action

Inline actions are actions that are created within a smart contract. A single action that a user authorizes can then create many subsequent actions that will execute within a single transaction, or create deferred transactions as well.


It is a distributed storage mechanism for putting files online for decentralized storage.


Issues are a great way to track tasks, improvements and bugs for your projects through the GitHub platform.



Is a lightweight and flexible command line to process JSON files.

Jungle Testnet

The Jungle TestNet was initiated by and has served as sand box for many development teams and EOS Block Producers since the birth of EOSIO.



A Kanban board is a tool that allows us to visualize a team workflow, creating columns with the most important stages of project development. It assigns tasks to team members, allowing a better organization of time and resources.


It works as a wallet to handle the keys for EOSIO. It is the component that securely stores EOSIO keys in wallets.

keosd = clave + eos


Kubernetes is a portable, extensible, open-source platform for managing containerized workloads and services, that facilitates both declarative configuration and automation. It has a large, rapidly growing ecosystem. Kubernetes services, support, and tools are widely available.



LACChain is an initiative by IDB Lab (part of the Inter-American Development Bank) to accompany and accelerate the development of the blockchain ecosystem in Latin America. It aims to establish national consortiums in the region, to develop and promote standards for interoperability of networks, and to develop and maintain interoperable blockchain infrastructures.

LatamLink is a voluntary regional alliance led by Latin American technology companies. We develop an EOSIO-based testnet for the LACChain network to highlight the benefits of this technology. LatamLink deploys a public permissioned version of EOSIO technology for Latin American developers and organizations to test their decentralized applications and infrastructure.


Period of time that elapses between the communication of a packet through the network.


The term used to signify the beginning of a blockchain.

LIB (Last Irreversible Block)

A block is considered irreversible (i.e. immutable) on an EOSIO based blockchain when 2/3rd of the currently elected block producers have acknowledged it.



Mainnet is the main EOSIO blockchain under the ChainID: aca376f206b8fc25a6ed44dbdc66547c36c6c33e3a119ffbeaef943642f0e906.

Since EOSIO software is open source and available for free, there may be many instances of it.

Merkle Tree

A Merkle Tree is a tree in which every leaf node is labelled with the hash of a data block, and every non-leaf node is labelled with the cryptographic hash of the labels of its child nodes. Hash trees allow efficient and secure verification of the contents of large data structures.

Micro Fork

A microfork occurs when a Block Producer begins to produce blocks with the same block height as a block that was recently produced.


Multisig is a short term for multiple signatures.It’s used to describe the case in which one requires more than one account's permission to execute a transaction.



NET is a very important resource in EOSIO based blockchains. It is the network bandwidth (measured in bytes) required to store transactions on a blockchain.


Is the core EOSIO node daemon that can be configured with plugins to run a node. Example uses are block production, dedicated API endpoints, and local development.

nodeos = node + eos


node is the fundamental basis of blockchain technology, they make up the infrastructure of a blockchain. All nodes in a blockchain are connected to each other and constantly exchange the latest data in the blockchain so that all nodes are kept up to date.


NPM Node Package Manager is an online repository for publishing open source projects, it also allows the installation of packages, version administration and dependency administration.



An oracle is a system that makes off-chain data available on-chain. An example of this would be an oracle that takes the score of a basketball game and puts it on-chain for smart contracts to consume and base decisions on.

Owner Permission

Within the permissions structure of an account, owner is the top-level authority. The owner permission can sign on behalf of, and restructure, all lower-level permissions. It is one of two default permissions that come with a new account, owner and active.



A weighted security mechanism that determines whether or not a message is properly authorized by evaluating its signature(s) authority.

Podcasts EOS

A set of EOS-related sites where new content is constantly being added to channels. This content can be in video, audio, or blog format.

Private Key

A private key is a secret key used to sign transactions. In EOSIO, a private key's authority is determined by it's mapping to an EOSIO account name.

Proof of Work

Proof of Work is a consensus mechanism used by many blockchains, most notably by Bitcoin. The miner of the next block is the first to solve a hashing problem. The difficulty of this problem increases as more hashing power attempts to solve this problem at the same time. The ever-increasing amount of work that has gone into a blockchain over time is what protects the chain's history.


The actual act of delegating your vote towards another account. If a user does not want, or have the available time, to research which Block Producers should receive their vote (but still wants to participate in voting), they can proxy their vote strength towards another account.

Public Key

A publicly available key that can be authorized to permissions of an account and can be used to identify the origin transaction. A public key can be inferred from a signature.

Pull Request

Pull requests let you tell others about changes you've pushed to a branch in a repository on GitHub.

Once a pull request is opened, you can discuss and review the potential changes with collaborators and add follow-up commits before your changes are merged into the base branch.




RAM is required to store account information such as keys, balances, and contract state on an EOSIO based blockchain.


EOSIO accounts have three types of resources that they must maintain: RAM, CPU and Net.


The REX (Resource Exchange) is a CPU and Network resource rental market in which holders of the core token of a blockchain can buy and sell slices of the REX pool in the form of REX tokens. Blockchain users can then rent CPU and Network resources from the REX pool.

Ricardian Contract

In the EOSIO based blockchain context Ricardian Contract is a digital document that accompanies a smart contract and defines the terms and conditions of an interaction between the smart contract and its users, written in human readable text, which is then cryptographically signed and verified. It is easily readable for both humans and programs, and aids in providing clarity to any situations that may arise in the interactions between smart contract and its users.


Smart Contract

A smart contract is a computer protocol intended to facilitate, verify, or enforce the negotiation or performance of a contract.


At any given point in time, a Snapshot of the total state of the chain can be taken. For example, this could be used by a token that wants to airdrop to all current token holders based on their current holdings.


Part of a system that if it fails to detect the operation of the entire system. These are not desirable in any system with a goal of high availability or reliability.

Squash Merge

Squash merging is a merge option that allows you to condense the Git history of topic branches when you complete a pull request. Instead of each commit on the topic branch being added to the history of the default branch, a squash merge takes all the file changes and adds them to a single new commit on the default branch.


A tokenwhose value is intended to remain stable. This can be done by pegging to another currency or token, or algorithmically. Many stablecoins peg to the US dollar, meaning that one token should always be redeemable for one US dollar.


Your total EOS token holding is referred to as your stake.

Standby BP

A set of about 100 full nodes that have expressed the desire to be selected as block producers, and are capable of doing so on demand. Whenever the chain needs to replace an existing BP with a new one, the new one is drawn from the standby pool.


StoryBook is an open source tool for developing UI components in isolation for React, Vue, and Angular.

System Account

These are accounts that begin with the prefix eosio.* and hold either the code or the funds for native blockchain actions (such as voting, multisig, account creation, and so on).


TaPoS - Transaction as Proof of Stake

TaPoS is used to ensure that a user fetches the recent state of the top of the blockchain to prove that they are aware of the state of the chain when signing a transaction. This helps to prevent certain forms of attacks, such as a replay attack where a malicious user tries to replay a transaction, despite the state of the associated accounts having already been changed.


Telos is a blockchain platform without high-performance permissions for decentralized applications with advanced data storage and governance functions.


Terraform it is a tool to build, change and version infrastructure in a safe and efficient way. Terraform can manage existing and popular service providers as well as custom internal solutions.


A test network or testnet is an instantiation of the EOSIO platform that is intended for testing purposes. Generally, the native token has no value and is given away to developers so they can test.


The unit of measurement of a cryptocurrency.


A metric by which the performance of a blockchain is measured.


It is a combination of one or more actions. Usually the result of executing a smart contract.


UAL (Universal Authenticator Library)

Developed by EOSIO Labs, the Universal Authenticator Library (UAL) allows app developers to integrate with a variety of authenticators (wallets, app explorers, key managers, etc.) by coding to a single, universal API.

UX Design

It is the design process that development teams use to create products that provide enjoyable experiences for users.



Voting is a fundamental part of the system. The most widely used application of voting is to elect which Block Producers will actually produce blocks for the network. Voting will also be used to help collect the communal decisions through which we will change the course of the network.

Vote Decay

To discourage users from casting a vote for Block Producers and then not updating their vote periodically, a decay in the relative vote strength of old votes was introduced. To maintain maximum vote strength, a user should vote at least once per week.



Wallets are clients that store keys that may or may not be associated with the permissions of one or more accounts. Ideally a wallet has a locked (encrypted) and unlocked (decrypted) state that is protected by a high entropy password.


The EOSIO based blockchains execute user-generated applications and code using WebAssembly.

WASM is an emerging web standard with widespread support of Google, Microsoft, Apple, and others. At the moment the most mature toolchain for building applications that compile to WASM is clang/llvm with their C/C++ compiler.


Makes references to a chip holder who has a very big bet.


A whitelist is a subjective measure that a blockchain node can implement to allow transactions to be placed in a block only if they are listed in your account or contract whitelist. Each node can specify its own whitelist, which cannot be seen publicly.

WPS (Worker Proposal System)

It is a system through which community funds would be used to support blockchain improvements, community projects, and anything the community deemed worthy of public funds. It is configured to be financed through part of inflation.




Yarn is a package manager for web projects that supports the npm package manager structure (package.json y node_modules).



Zeplin is a collaborative tool for designers and Front-End developers that allows a workflow in which they can create designs, facilitating communication, and better organization of time.